My driveway here in Texas is very long and is an oilfield road to the pumpjack pad. They bring in river gravel every now and then to spread on the driveway. The rock is from that gravel that was put on the driveway. Since it is from a river gravel pit, most likely was an indian campsite dug up somewhere. Pit operator is not going to report that.
Since it is from a river pit, it was most likely a naturally worn stone. If a hunk of chert sat around in a village (which would be situated on a fertile loamy site overlooking a river rather than an infertile gravel bar down low) it would be converted to useful blanks and flakes pretty quick rather than be wasted as a grinder where a more common and more suitably shaped stone would do. This hunk of flint has a few bits knocked off of it but they look to be from random strikes. It is very clean and has a thin cortex from long being situated in a river amid countless other stones, that is, it hasn’t been stained from being the family mortar buried by itself for ages under layers of camp refuse and soil. Banner stones were usually slate, granite, or porphery, occasionally other materials, and the hole was bored into a bannerstone using river cane and chert grit, which makes a very regular hole perpendicular to the surface but bigger where the drilling begins and smaller where the drilling stops, and less than an inch across. Chert was preferred for knives, scrapers, drill bits, razor sharp cutting flakes, arrowpoints, and spearpoints.
That is pretty cool. Amazing what you can find when you move earth.